OpenVpn Server with pop3 Auth

Most organizations would prefer centralized auth. When a person resigned his / her email id is deactivated on priority bases, same can be done with openvpn. If same user is being authenticated from existing mail server, it will same time for sys admins to remove access from different places.

compile auth-pam from openvpn source

cd /root/openvpn-2.1.3/plugin/auth-pam
make
cp openvpn-auth-pam.so /etc/openvpn/

download & install pam_pop3

tar zxvf pam_pop3-1.0.tar.gz
yum install gcc pam-devel -y
cd pam_pop3
make
cp pam_pop3.so  /lib/security/

append following in server.conf

plugin /etc/openvpn/openvpn-auth-pam.so "pop3"

Content of pop3 pam.

cat /etc/pam.d/pop3
auth    required        /lib/security/pam_pop3.so hostname=pop.linuxreaders.com info pwprompt=Passwort: timeout=20
account    optional    pam_permit.so

This is all needs to be done at server end. at client end append following line in client.conf

auth-user-pass

Now, while connecting you’ll get prompt to enter username & password. No need to enter domain name. e.g @linuxreaders.com